Plasma blasting technology (PBT) refers to a technique of blasting a material using a high-power electrical discharge into that material. U.S. Pat. No. 5,106,164, which is hereby incorporated by reference, describes and claims such a technique. The implementation of this technology on the field requires several components, the main components being an electrical power source, an electrical energy storage module, a switch, a transmission line, and a probe assembly. The first 4 components, which are involved in the storage and delivery of the electrical energy, are all commercially available. However, very little information is available on the most critical component, namely the probe assembly. The probe assembly is the piece of equipment that is in direct contact with the substance to be blasted and, therefore has to withstand the mechanical shock associated with the blast.
A probe assembly is disclosed by O'Hare in U.S. Pat. No. 3,679,007. This probe was developed for drilling boreholes, and therefore, little energy is required for each blast. Energy can be computed using the following formula: E=(CV.sup.2)/2, where E is the energy (in Joules), C is the capacity of the capacitor bank in (Farads), and V is the voltage across the capacitor bank (in Volts). In U.S. Pat. No. 3,679,007, it is specified that a 400 microfarads capacitor bank functioning at 6,000 volts, yields an energy of about 7,200 Joules.
There is however a great need for a probe assembly designed to actually blast a substance or material. To produce such a blasting effect, the probe must liberate a tremendous amount of energy in an extremely short period of time. To be of commercial interest, the probe assembly must therefore be able to provide such high amount of energy quickly, while simultaneously sustaining the high impact or shock caused by the fast liberation of energy. The probe assembly should be designed to resist to a plurality of blasts, preferably more than 500, before being replaced. The present application describes and claims a probe assembly having these properties.